The earliest windmills were mainly designed to grind grains for food production, but this breezy machinary has been adapted for many other industrial uses over the ages. The most recent incarnation of this technology converts wind power into a renewable energy source. Wind farms currently supply 3 percent of U.S. electricity, though that number is expected to jump to 30 percent by 2030.

Practical uses aside, these machines are also an aestheically surreal (and in many people's opinion, gorgeous) addition to many of Earth's landscapes.